Allow t.similar(str, regexp) to work as expected

lib/tap-assert.js

@@ -220,15 +220,32 @@ syns.inequivalent = ["notEquivalent"
                     ,"isNotEquivalent"
                     ,"isInequivalent"]
 
-function similar (a, b, message, extra) {
+function similar (a, b, message, extra, flip) {
   if (extra && extra.skip) return assert.skip(message, extra)
   // test that a has all the fields in b
   message = message || "should be similar"
 
-  var isObj = assert(a, message, extra);
-  if(!isObj.ok)
-    return isObj;
-  return equivalent(selectFields(a, b), b, message, extra)
+  if (typeof a === "string" &&
+      (Object.prototype.toString.call(b) === "[object RegExp]")) {
+    extra = extra || {}
+    extra.pattern = b
+    extra.string = a
+    var ok = a.match(b)
+    extra.match = ok
+    if (flip) ok = !ok
+    return assert.ok(ok, message, extra)
+  }
+
+  var isObj = assert(a && typeof a === "object", message, extra)
+  if (!isObj.ok) {
+    // not an object
+    if (a === b) isObj.ok = true
+    if (flip) isObj.ok = !isObj.ok
+    return isObj
+  }
+
+  var eq = flip ? inequivalent : equivalent
+  return eq(selectFields(a, b), b, message, extra)
 }
 assert.similar = similar
 syns.similar = ["isSimilar"
@@ -239,10 +256,8 @@ syns.similar = ["isSimilar"
 
 function dissimilar (a, b, message, extra) {
   if (extra && extra.skip) return assert.skip(message, extra)
-  // test that a has all the fields in b
   message = message || "should be dissimilar"
-  a = a && selectFields(a, b); // Always send selectFields() usable params.
-  return inequivalent(a, b, message, extra)
+  return similar(a, b, message, extra, true)
 }
 assert.dissimilar = dissimilar
 syns.dissimilar = ["unsimilar"